Development of dish-based population-specific food frequency questionnaire for dietary assessments in Afghanistan

Introduction

Dietary intake assessment has an essential role in chronic disease studies and general public health outcomes.^1–3 Improving dietary habits along with environmental and lifestyle factors, is a major target in the prevention of non-communicable diseases (NCDs), such as cancer, cardiovascular diseases, diabetes and chronic kidney diseases.^3,4 NCDs are rapidly increasing in low-income and low-middle income countries.⁵ The potential causes of this rising burden need more investigations and taking preventative policies by the governments.

It has been demonstrated that long-term dietary intakes affect the risk of chronic conditions.³ To measure dietary intakes in epidemiologic studies, various dietary assessment methods are used such as 24-hour recalls, food records or diaries and food frequency questionnaires (FFQs).^6,7 Methods such as 24-hour recalls and food records are associated with high subject burden.⁸ FFQs can provide useful measures of dietary intakes.⁷ It has widely been used in investigating the association between diet and chronic diseases in large population-based studies.^9–13 The advantage of this method includes its easy application, low respondent burden, self-administered method of use, less training of research staff and assessment of diet for long-term.^12,14 Besides providing information on usual intakes of a particular food or a food group of interest, FFQs are particularly useful in identifying dietary patterns at the population level.¹⁴ Measurement errors, which refer to the difference between reported dietary intake over a specified time period and true usual dietary intake, that might result in participants’ misclassification in terms of dietary intakes is a big concern in FFQ.¹¹ These errors can arise from the incomplete list of foods included in the questionnaire as well as inaccurate portion sizes.

Despite the availability of many FFQs in the world, there is a great variability in the foods consumed and in dietary culture in diverse populations.^15–17 A FFQ which is valid for one population may not be valid when applied to a second population.¹⁸ On the other hand, most information on diet-disease association came from western and developed countries and such information is scarce in developing countries¹⁹ and to the best of our knowledge almost nothing in Afghanistan.

As the burden of chronic diseases is increasing worldwide,²⁰ the contribution of dietary intakes to such increasing trend is important.²⁰ To examine diet-disease associations in Afghanistan, development of a FFQ to measure long-term dietary intakes is mandatory. This study is therefore aimed to report the development process of a population-specific DFFQ to assess long-term usual dietary intakes in Afghanistan.

Methods

Ethics approval and consent to participate

This study was approved by Tehran University of Medical Sciences (TUMS) ethical committee with approval ID: IR.TUMS.VCR.REC.1399.567 on March 17, 2020. Written informed consent was obtained from all study participants. The Helsinki Declaration is considered through all stages of this study and all methods were carried out in its accordance.

Development of the DFFQ: In the current study, the Willett format was applied to develop a population-specific DFFQ for Afghanistan.¹⁴ Commonly, FFQs are used for the purpose of ranking individuals according to food or nutrient intake rather than for estimating absolute amounts of intake.¹⁵ Meanwhile Willett’s FFQ, using a close-ended format, was developed with the primary objective of ranking individuals according to their usual dietary intake²¹ but Block’s instrument was developed in the open-ended format to rank individuals as well as to estimate the absolute intake of several nutrients.²¹ Therefore we preferred Willett format rather than Block Format for development of current DFFQ. This effort was done to develop a suitable dietary assessment tool to examine usual dietary intakes in adult people in Afghanistan. The questionnaire was developed by taking the following steps. First, we listed commonly consumed Afghani foods. Then, food groups were determined and definition of portion sizes was done. Finally, frequency response options for each food item were defined. The development process of this DFQ is summarized in Figure 1. Here, we describe each step in detail:

Figure 1. DFFQ development process.

Food list construction: First, we created a comprehensive list of foods and dishes commonly used in Afghanistan, based on the information we took from local people. Twenty adult volunteers (18-60 years old), including women, were selected from various regions of Kabul City. We requested that they sign an informed consent letter and provide a list of their usual consumed foods at different meals (breakfast, lunch, dinner and snacks) throughout the year. This was an informal survey based on convenience sampling. Paper forms were given to the participants. The form had a consent statement and 30 blank spaces for writing the names of the foods. They took the forms to their homes and then returned them within three days. The survey was conducted in February 2021. We collected the forms within two weeks. After collecting the forms, all food items and dishes based on this informal survey were listed. This method was done in order to prevent missing major food items in different meals. Based on this listing of foods, we found that Afghanistan populations mostly consume mixed dishes. For example, Afghans consume meat in the form of several mixed dishes such as Kebab, Kofteh (meat balls), Manto, Dopiazeh, Qabli etc. Indeed, it is too difficult to estimate total meat intake of a person in the preceding 12 months, because the frequency consumption of meat in such a long period of time is extremely hard for participants to remember. Estimating the usual intake of meat from various origins would be very difficult for a person and might confuse participants. In addition, it is likely that some dishes containing meat will be neglected. On the other hand, estimating the quantity and frequency of consumption of each dish is rather easy. Therefore, we aimed to design a dish-based FFQ rather than a food-item based questionnaire because it is difficult for people to assess their usual intake of ingredients in mixed dishes. Previous studies showed that questionnaire length has an important role in the survey response rate, as lengthy questionnaires may cause exhaustion and decrease the cooperation of participants.^13,22,23 As Afghanistan people consume different mixed dishes, including all ingredients of these dishes would make the questionnaire too lengthy. Therefore, in order to shorten the DFFQ and facilitate responding, we have included dishes and collapsed together some other dishes that have the same ingredients.

Foods and dishes that were nutrient-rich were included in the food list. In other words, nutritious food and dishes were included in the list. In addition, foods and dishes that had considerable contribution to between-person variation were also included. To find such foods and dishes, we discussed all foods and dishes in our prior comprehensive list and then selected the ones that might be different in different regions of the country. Then, a group of health specialists from Afghanistan discussed all the items and the foods rarely consumed were not included in the questionnaire. Finally, 103 food items or dishes were selected (Table 1).

Table 1. List of food and dishes included in the dish-based food frequency questionnaire for Afghanistan.

Food and Dishes	Mantu, Aashak, Aash, boiled egg, half-baked egg, Soup, Bamia, fish conserve, fish, Potato qurma/burani, Fasiliya, eggplant qurma/burani, Shula, Qabli palaw, Mash palaw, Kichri qurut, Qurti, cauliflower, Kufta (meat ball), Bulani gandana, Bulani kachalu, Bulani kadu, Fried chicken, Chicken qurma, Kadu, Shurba landi, Shurba kala-pacha, Shurba cow meat, bean, Macarani, Sabzi palak, egg piyawa, Kebab teka/karayee, Shurba sheep meat, Adas, Chapli kebab, Shirbrinj/ferni, bean conserve, Dal/dalnakhud, Nakhud conserve, Chynaki
Fruits	Watermelon, melon, tangerine, banana, apple, pomegranate, kiwi, grapes, apricots, cherries, plum, peach, fig, pear, mulberries, persimmon, mango, almonds, raisins, pistachio, date, walnut, dried berries, dried fig
Vegetables	Tarkari, onions, green pepper, cucumber, carrot
Breads	Oily bread, Ozbeki bread, Tawagi bread, Paraki bread, Tanduri bread, Dashi bread, Bazaari bread
Dairy products	Yogurts, whey, milk, cheese, butter, Qaimaq
Sweets	Julbi, jam, Kulcha/cakes/rut, Roghan joshi, chocolates, other kinds of sweets
Beverages	Soft drinks, energy drinks, juices, green tea, black tea, sweetened tea, coffee
Miscellaneous	Pizza, burgers, chips, turshi, ice cream

Determination of food groups: To simplify the questionnaire, we divided the dishes and food items into eight main categories: 1. Prepared or canned mixed dishes, 2. cereals 3. Dairy products, 4. Sweets, 5. Fruits, 6. Vegetables, 7. Beverages, and 8. Miscellaneous food items.

Portion size determination: After determination of food groups, we discussed the portion size section. There was much diversity observed in food and dishes portion sizes common among Afghanistan people. In addition, common portion sizes may vary from one region to another. However, portion size estimation does not make significant contributions to between-person variation in food intake and may not serve to a more accurate ranking of individuals based on their dietary intakes, several well-designed FFQs in the world have portion size section.²² The current DFFQ defines portion sizes for each food item and mixed dish based on the portion sizes most frequently used and understood by the Afghanistan general population. Common portion sizes for each food item and a certain dish was discussed by a group of local health specialists. To make sure that public people understand the units and portion sizes in the questionnaire, we administered the preliminary DFFQ to a group of volunteers in Kabul, Afghanistan as a pilot test before its finalizations.

Frequency response options: According to FFQ of Harvard,²⁴ we introduced multiple choice frequency response options to facilitate responding. Each food item’s frequency response options were defined separately in a row against the food list, rather than mentioning them in a column at the top of the page. Although this is different from the one used in Harvard FFQ,¹³ we believe that this can result in reducing errors in estimating frequency of foods and dishes consumed. The categories we used in this questionnaire varied from “never or less than once a month” to “6 or more times per day”. Participants should indicate their average frequency of consumption by checking 1 of the 9 frequency categories. The number of frequency response categories is not constant for all foods. For frequently consumed foods, we included 6-9 options and for infrequently consumed foods, we omitted options of high frequency.

Food and nutrient intakes calculation: As mentioned above, the developed DFFQ consisted of foods and dishes with standard portion sizes, usually consumed by Afghanistan people. To compute nutrient intakes from this newly developed DFFQ, we will convert all reported consumption frequencies of foods into grams per day by using household measures. To convert dishes into grams, first we listed the ingredients of the dishes listed in our DFFQ. The ingredients of the dishes were discussed in a group of 3-4 local housewives and their consensus on ingredients was considered as the final ingredients of that specific dish in Afghanistan. To identify nutrient intakes for each individual, we converted all foods and dishes in the questionnaire to 103 individual foods. Then, using Nutritionist IV software, we computed total calories, macronutrients and micronutrients for each individual by summing up nutrients from all foods.

Results

In the current study, we reported the strategies used to develop a new population-specific DFFQ in Afghanistan (Figure 2). FFQs are used to assess long-term dietary intakes in epidemiological studies, and they should be population- and culture-specific. Therefore, a FFQ from one country cannot be used in another due to the difference in dietary intakes and food cultures. Given the lack of any FFQ in Afghanistan, we developed this DFFQ, which can be used for any epidemiological research focusing on diet and nutrition, particularly when the study objective is to evaluate the long-term dietary intakes of the Afghanistan population and when investigating the relationship between diet and disease. However, it must be kept in mind that the current study reports only the development of this DFFQ, and currently there is no data on its validity. The validation study of this new DFFQ is underway, and the findings of the validation study will be reported in the near future.

Figure 2. A sample of food items included in the designed food frequency questionnaire.

Discussion

Many culture-specific FFQs have been developed to evaluate the dietary habits of culturally diverse population groups.^25–29 Designing a culture-specific FFQ includes some main steps, namely development of a complete and precise food list, determination of culture-specific food groups, and the definition of culturally appropriate portion sizes. Therefore, considering other studies,^25,26,30,31 our methodology was based on the above-mentioned guideline. The questionnaire was designed based on Willett-format,¹³ included 103 food items and mixed dishes along with appropriate portion sizes.

The FFQ has widely been used in investigating the association between diet and chronic diseases in large population-based studies.^9–11,13 It is easily applicable and can reflect long-term usual dietary intakes. Although the accuracy of data from this type of dietary assessment method is lower than other methods, its low cost and easy-to-use format along with reflecting usual long-term dietary intakes has made this dietary assessment tool as an appropriate method in epidemiologic studies.¹⁴ It is also useful in identifying dietary patterns at the population level.¹⁴ Measurement errors, incomplete list of foods and inaccurate portion sizes have been considered as potential disadvantages of FFQs.¹¹

The primary objective of this study was to report the development process of a population-specific easy-to-use comprehensive DFFQ for assessment of dietary patterns and diet-disease association in epidemiological studies in Afghanistan. Considering the use of several mixed dishes in Afghanistan and low literacy of public in the country, we decided to design a dish-based questionnaire because most people, in particular men, are not aware of ingredients of the dishes.

Furthermore, accuracy and precision of data collection may be improved by inclusion of dishes in the list of FFQ food items due to the following two reasons.³² First, Non-communicable diseases (NCDs) are related to culture-specific cooking methods and ingredients.^32–34 Second, people may not report invisible components of a mixed dish in the FFQs without dishes because they are neither contributed in their cooking process nor can see the ingredients of different recipes. As a result, they cannot remember the consumption of mentioned foods.³⁵

Earlier studies in Iran, with a very close culture to Afghanistan, have also reported the development of a dish-based FFQ for assessment of dietary intakes. The same activity was also done in Korea, Bangladesh and Iran.^{15,23,35–37} Almost all available studies have shown that DFFQs can facilitate the evaluation of dietary intakes over a long period at populations with a high consumption of mixed dishes.^23,35 The DFFQ we developed in the current study contained 103 items (28 mixed dishes and 75 food items), while the one in Iran had 106 and 142 items.^15,35 Number of foods and dishes in the DFFQs developed in Bangladeshi and Korean was 42 and 112 items, respectively.^23,36 We tried to develop a comprehensive questionnaire for assessment of dietary intakes. This is also the same for the questionnaires developed in Iran. However, the variability in the number of food items might be due to the cultural difference in the consumption of varied foods and dishes in a specific country as well as the main purpose of the investigators.

In the present DFFQ, we followed the Willett format.¹³ However, the frequency response options in this DFFQ were included in a row against each food item which is in contrary to Harvard Format.²¹ The Willet format is widely used in FFQs developed in other parts of the world due to its easy application. The same approach has also been used in Iranian Dish-based FFQs with cultural similarity to Afghanistan.³⁵ However, it provides categorical data, which might not provide enhanced precision in reporting dietary intakes.¹³ The main limitation of this DFFQ is that it has not been validated yet, and we are currently working on its validation.

Conclusion

We developed a new population-specific DFFQ in Afghanistan, which can be used as an instrument for assessment of long-term dietary intakes as well as diet-disease associations in Afghanistan. The next step should be assessment of validity and reproducibility of this questionnaire before using it in large scale studies among Afghanistan population.